Portable radio receiving set



Feb. s, 1927.

H. CSANYI POR-TABLE RADIO RECEIVING SET Filed Deo. '7l 1922 H yf ,7 M

' IIE,

/N VEN TOR Paieisar'en a; 1927.

HENRY-Ceann, or NEW Yonx, 'n'. Y.

PORTABLE RADIO RECEIVING SET.

Application led December This invention relates toa radio receivingapparatus, and more particularly to a hand- '-portable radio receiverunit especially designed for broadcasting reception; and has specialreference to the provision of a combined unitary radio receiving set andtelephone receiver.

A principal object of my present invention comprehends the provision ofa radio receiving apparatus built into a compact and unitaryorganization on the style of the ordinary telephone receiverfandoperable when connected to an antenna for eiliciently receiving radiotelephonie energy.

In the construction and-design of a complete radio receiving outtadapted to be carried in'the hand and applied to the ear after thefashion ofthe ordinary telephone receiver, a number of problems presentthemselves for consideration, upon the successful solution of whichlargely depend t-he Workability and eliiciency of the radio receivingunit. The receiver unit in being hand-portable and of a size comparable/with the common telephone` receiver, must comprise but a fewpartscompactly organized and eliiciently coordinated. To minimize bulk, it isdesirable to'avoid the use of all energy sources in the receiving setsuch as 33 batteries, and the parts of the radio outfit must be soselected and arrangedmsto per niit`of efficient reception'of incomingradio f impulses, with the production of strong audible impulses Withoutthe use ofy such energy at the incoming station. It is also highlydesirable to overcome such disturbing influences as the proximity ofgrounded bodiessuch as the presence of the users o hand in holding thereceiver unit or the desiderata in the production of an apparatus ofthis nature are the provision of a .unit

which is substantially free from accidental derangement or settingdisturbanceywhich is rugged so as' to withstand rough usage, and vwhichis constructed in a lmanner to be quickly disassembled for purposesofreplacement and re air, with'parts standardized to ,permit rapi andinexpensive re lacement'. My present -invention comprehen s theprovision of a portable and. unitary receiving set in which thesefeaturesare --present in a high degree and are combined in an ecient'manner. to effect a workable apparatus 55 capable of eilicient radioreception.'

users head` to which it is applied.' Other- 7, 1922. serial No. 605,462.

To provide a compact hand-carried set, l have found it desirable tocombine with1 va .telephone receiver such radio. receiving parts as atuning coil, a detector, and if desired a condenser, all'connected in asimplified circuit. A common objection to a simplified receiving set ofthis nature is v,that the set is not sensitive enoughfor receiving therelatively Weak impulses intercepted by an antenna. I have found afterextensive experi-mentation that this objection may be successfully7overcome, and that the receiver parts ma be so co-ordinatedandrelatively associate as to produce a unit which vsensitively respondsto incoming radio impulses such as Vare transmitted from radiobroadcasting stations; and one of the principal objects of my inventioncomprhends the provision `of a receiving apparatus which is efectivelyresponsive to relatively weak radio frequency energyfor producing strong.audible impulses. .y

It is Well known that the tuning of a radio set is greatly influenced byproximate grounded bodies, and is detrimentally disturbed by the changein position vor location of such grounded: bodies, the tuning being.` I

largely influenced, for example, by themovement of such objects `as thehand' or body -of the operator. This is especially the case where-theentire set isv carriedrinthe hand .of the operator, and for thesuccessful operation of a hand-carried radio receiver the effect ofground bodies must be largely eliminated. The provision of an apparatusof this nature which is substantially free from ground influences., ofthis kindl is another principal object of my present invention. f

Themore speciic'objects of'my present invention may be said to include,besides the provision of a unitary hand-portable apparatus having thecharacteristics above re' ferred to the further provision of a.handcarred radio receiving unit in which the telephone. Icoil, thetuning coil and the detector are coaxially. arranged with the de` tectordisposed within the tuning coil land arranged soas toy be induenceduniformly by the magnetic field thereof; the further provision of a.unit of this nature inwhich all the parts ofthe receiver are'containedinl a casing, this casing functioning as 'an electrostatic. shield forthe parts of the ap' Aparatu'sct'ntafinectherem.;v lthe furtherprofvvisionof a unit ofthis nature in which the vision of a crystaldetector unit constructed so as to ipermit quick detachment andreplaceability thereof; the further provision of a novel crystaldetector plug; eral provision of a receiving outfit comprising few partscombined in a simple way to produce a unit manu cturable at a loW costand saleable at a moderate figure.

Another object is the provision of --a construction wherein the detectorcontact or catis Whisker is so arranged and of a character such that themagnet acts upon the contact in the manner of an interrupter.-

To the accomplishment of the foregoing and such other objects as mayhereinafter appear, my invention consists in the elements and theirrelation one to the other, as hereinafter particularly described andsought to be defined in the claims, reference being had to theaccompanying drawings showing pre.- ferred embodiments of my invention,and in which:

Fig..1 is a cross-sectional view of the com- .plete radio receivingunit.

Fig. 2 is a rear elevational view thereof,

Fig. 3 is a cross-sectional view taken on the line 3 3, Fig. 1,

Fig. 4 is a cross-sectional view thereof on the line 4 4, Fig. 1,

Fig. 5 is a wiring diagrammatic View showing the electrical connectionof the parts and the manner of connecting the same for radio energyreception, and

Fig. 6 is a wiring diagrammatic view showing a modification thereof.

Referring now more in detail to the drawings, the radio receiving unitof my invention preferably comprises a telephone receiver 'A which mayinclude-a plurality of telephone coils 10 and a diaphragm-11, a tunlngcoil B, and a detector such as a crystal detector C, all carried by andhoused within a casing 12, the telephone receiver A being located at oneend of the casing and the tuning coil B and detector C being lo-4 catedwithin vand at the 'opposite end of the said "casing, the casingy 12being externally threaded at one end, asat 13, for receiving thecorrespondingly threaded cap 14 of the type commonly employed withtelephone receivers. l

The telephone receiver A in the preferred construction includes theplurality of receivin coils 10 carried by the core pieces 15 which aresecured tothe arcuate members 16'by the securing means such as 17,these. arcuate members being attached to an emma and the geni terasselar member 18 by the' securing yelementl), y

the lsaid annular' member being receivable by an annular recess 20provided in the front interitted as to permit the positionin of thediaphragm 11 adjacent the pole grecs of the cores of the telephonereceiver, with the parts clamped in position by the mountinof the ca 14on the casin 12.

s hereto ore mentioned, have found -afterconsiderable experimentationvthat thev parts of the receiving set maybe so4 co-A related as toproduce a unit which sensitively responds to incoming radio frequencyimpulses such as are transmitted from radio broadcasting. stations. Morespecifically. l have found thatv the tuning coil B and the detector Cmay( be so relatively disposed within the casing 12 as to effect thestrengthening of the audible impulses pro duced, this resultv beingachieved by the disposing of the detector C longitudinally within thetuning coil B and influenced by the magnetic field thereof, these partsbeing preferably co-axially arranged at the rear end of the casing 12.ln the vpreferred construction the tuning coil B comprises a multi-layercoil 21 as'clearly shown in Fig. 1 of the drawings, wound upon a spoolbody 22k of insulating material, detector C' being disposedlongitudinally within the magnetic field of said coil and being arend ofthe casing 12, and these parts are so 'A ranged coaXially therewith soas to form the core thereof. Desirably the tuning coil B and thedetector C are arranged coaxially with the telephone receiving coils 10,as is clearly shown in the drawings. By the provision of thisarrangement, it has been found that the sound impulses may be materiallystrengthened soas to eect a more sensitively responding receiving unit.

The detector C in the preferred construction lcomprises a crystaldetector providing acrystal such as 23, which may for example be acrystal of iron pyrites,v and a detector contact or point 24 cooperatingA therewith, the crystal and point being so co-ordinated as to minimizethe possibility of accidental displacement of the parts after the samehave been set in a given position in the assembling thereof. In theassembling of the crystal parts, a point of the crystal is selectedwhichyields the best results, and-a'desideratum of thepresent inventionincludes the provision of a construc tion in which the accidentalrelative disl lacement of the detector parts is effectively prevented sothat the selected point will remain substantially the same under allconditions of service to which the receivino` unit is subjected.` Afurther desired end 1n the construction of the crystal detector is' therevision of a detector unit which besides ing free from mishandling, iscapable of quie detachment from the receiving unit -for purposes of.repair or replacement. To these ends, the crystal detector of myinvention comprises, a separable plug includs ing an insulating plugbody provided at one end with a recess 26 housing the crystal 23, thesaid recess being' closed by a threadedmember 27 contacting the crystal23, andi provided at the other end with a re-l cess 28 housing theflexible part of the contact 24, the said recess being closed by althreaded member 29 to vvhich the said contact 24 is electricallyconnected, the said plug body being further provided with Va constrictedopeningl30 vconnecting the two recesses 26 and 28, the constrictedopening being designed vto minimize any vibration of the contact 24 soas to prevent displacement thereof and derangementof the Contact pointselected, While permitting an initial. setting in theassembling thereof.The plu" body 25 and the end threaded `members 2 and 29 comprise ahousing for the detector parts, the Whole forming a plug unit whichk isquickly separable and replaceable' in the.

2 receiver unit, as will appear morefin detail hereinafter.

As heretofore mentioned, for the purpose of preventing any interferenceWith the tuning of the receiving set such as'result's from the change inposition of proximate ground- -I ed bodies, my invention includes theprovi'- sion of means vfor electrostatically shielding the parts of thereceiving unit so that the unit may be carried in the hand of the userand maybe tuned without ground disturbances. To this end the casing 12comprises a metallic casing, and the parts of the unit? are so connectedto the metallic casing asq to be electrostatically shielded thereby.VThis" b may be accomplished as shown in the drawings by-making thecasing 12 the ground terminal of the receiving set and appropriatelyconnecting the parts of the set thereto. For connecting the' parts asdesired, I provide a metallic plate'30 which is'connect- I ed to theinsulating coil body 22 by means ofy the securing elements 'such as 31,the said metallic plate being electrically connected to one terminal of'the telephone coils 10 by means of a lconductor 32- connecting 4a'seycuring means 31 to a binding-post 32u insnlatablyl ixed on theannularmember v18 carrying the telephone coils, to which binding post'one of the terminals of the coils 10.

is connected as shown in Fig. 3'of the .draw-.f ings. The metallic plate30 forms one terminal of the crystal detector C, the. threaded'4 member27 being to this end threadedly re- 60"ceived by a central tapped bore33 Qin, the

said plate. The other terminal of the crys-l tal detector C iselectrically connected to the metallic casing 12 by means of the-cap -34which is threadedly received 'by the casing 12 and which contacts'thethreaded terminal 29 ofthe detector plug. The multi-layer tunlto theantenna and ground are diagraming Coil 2i is Similarly countered #nl@naar to the ground casing 12, one end of the v tuning coil beingconnected by Ameans of a conductor 35 to aconductor 36 `connected to'the binding post 37/which in turn'i's connect-` the tuning coi1u21beingv` connected to the casing 12 by' means of a 'movable arm 38electrically connected at its pivot 39 to themetallic/casing 12'andmovable over a plurality of spacedjpoints of the coi1'721 as will bedescribed diagramlnaticallyv hereinafter, the plurality of. taps beingprovided for tuning purposes, the winding of the coil and thearrangement of the taps being so designed as to permit adjustment forthe wave lengths of 360', l400 and 450 meters usually employed inbroadcasting transmission; r

For, connecting the set for radio reception, the conductor 36 leadingfrom thev binding post 37,'is connected to an aerial, and a conductor 41which is electrically .connected to the casing 12 by means, for example,of the screvv 42, yi'sconnected to some suitable ground'.

The electrical connections' between thereceiver parts and the connectionof the same matically illustrated in Fig. 5 of thc-drawings;y Referringto Fig. 5 the antenna A is shown connected by means of a conductor- 42atothe tuning coil 21 bymeans of theconductors. 36 and 35;, spacedlpoints of said tuning coil beingnnected as by means of 190 conductors43, 43"V and '43, 'to' the insulated buttons ortaps 40,.and 40, the tapsbeing selectively connected .to the casin0r 12v y means of themovablearm 38', the said casing being-'connected 'togrond G by means offthe"cenducto'r 41'; It will be further seen byreference to this' figurethat the tele- -ph'onejcoil and the crystal detector are\con nectedv.jin series. across ,the antenna and cally' shown in Fig. 6Fof thedrawing, and

having .reference to, this figure whichdia-4 grainlnati'ca'llyfv showsAthe receiver parts conncted to vtheantenna Af and .groundv G in a mannersimilar to thediagra'mmatic showing of Fig. 5', I show the provision .ofthe conductors or leads45sail1d 46 cannet-redt() 130 the conductors 32T'and-35- respecti.vely,l the ed to the receiver coils 10, the other endof, Q.

75, insulated taps 40240" and 440", connected to A 'd v'said conductorsbeing attachable to an auxilnected across the terminals of the coil 10by means of the conductors 49 and 50.

ln addition to providing a compactportable arrangement, the placing ofthe detector contact in the magnetic field in the manner specied`provides that the induction from the magnet will act in the manner ofan interrupter, giving a polarization on the same principle as thecoherer. As shown,

the detector contact has a coil, which is at the axis of the magnet.rlhis coil is a secondary with the magnet coil as a primary, and themagnetic induction provides vibration. While this vibration is veryfine, detectable only with a milli-ampere meter it .produces a higherrectification curve, and a steady rectification on the same point, sothat 1t is not' necessary to change the crystal point. i

Referring tok Figures 1, 5 and 6, it will be noticed that the coil inthe detector contact is at the axis of the magnet coil..-

The manner of making and using my portable radio receiving set will inthe main be apparent from the above detailed description thereof. ln theassembling of the parts the tuning coil and its mounting B carrying theplate 30 is inserted into the casing l2 and positioned at the innr endthereof,

- plus after which the telephone receiver A and its mounting with theterminals of the telephone coil ap ropriatelyI electrically ,connectedto the p` ate 30 and the tuning coil 21 is iitted into the front end ofthe casing .-12 :and clamped in position b the mounting of the #ea 14minthe saidv casing. The detector of the casing 12 by rotatin the same, the

4threaded Umember 27 `thereo being received by the plate 30, after whichthe cap 34 is threadedly inserted in the rear wall of thecasing v12 intocontacting position with the detectorlug.. The apparatus may then beconnected) vto an antenna and ground as shown in Fig. 5 of the drawin s,and may be adjusted within the 'range o broadcasting transmission bloperation of the arm 38. If the detector p ug is desired to be removedfor repair or replacement, the cap 34 .may

be unscrewed and the plu ,C removed as a' unit from the plate 30.

l he, telephone receiver coils and the tuning coil may be likemay thenbe inserted from the rear -V terasse the front cap 14 tor any desiredrepair or replacement. While l have shown my device in the prelferrediorms, it will be obvious that many changes and modifications may bemade 1n the structure disclosed, without departing from the spirit ofthe invention, dened in the following claims.

'l claim: i

l. A unitary and hand portable radio re-x ceiving set, comprising atelephone receiver with its coil and diaphragm, a tuning coil disposedadjacent the receiver coil, and a ixed crystal detector including acrystal and a detector contact cooperating therewith and arran ed at theaxis ofl the tuning coil.

2. A unitary and hand portable radio receiving set, comprising atelephone receiver with its coil and diaphragm, a tuning coil disposedyadjacent the receiver coil, and a fixed crystal detector including acrystal and a detector contact cooperating therewith and arrangedv attheaxis of the tuning coil,

the detector contactshaving a coil in theV length thereof. v

3. A unitary and hand portable radio receiving set, comprising atelephone receiver with' its coil and diaphragm, a tuning coil disposedadjacent the receiver coil, and a fixed vcrystal detector including v acrystal and a detector contact cooperating therewith and arranged at theaxis of the tuning coil, f

the detector contact havin a coil in the length thereof, and a meta 'ccasing housing the parts, the detector having one terminalelectricallyconnected to the receiver coil and the other tothe casing,the casing forming a connection for ground and an electrostatic shieldfor the receiving set.

4. A unitary and hand portable radio receiving set, comprising atelephone receiver with its coil and diaphragm, a tuning coil disposedadiacenti the. receiver coil, and a xed crysta detector. including acrystal .and a detector contact cooperating therewith and arranged atthe axis of the tuning coil,

the detector contact having a coil in the length thereof, the plughaving a restricted passage throu h whichthe end of the contact betweent e tuning coil'fand the crystal extends to limit vibration and preventdisplacement of the contact point.

Signed at New York city in the countyof York and State of NewYork'this29thv D. 1922.' f HENRY CSANYI.v

New day of November A.

